title: Long-term immunity against actual poxviral HLA ligands as identified by differential stable isotope labeling.
abstract: Viral peptides are presented by HLA class I on infected cells to activate CD8(+) T cells. Several immunogenic peptides have been identified indirectly by epitope prediction and screening of T cell responses to poxviral vectors, including modified vaccinia virus Ankara (MVA) currently being tested as recombinant or smallpox vaccines. However, for the development of optimal vaccination and immunomonitoring strategies, it is essential to characterize the actual viral HLA ligand repertoire of infected cells. We used an innovative approach to identify naturally processed MVA HLA ligands by differential HPLC-coupled mass spectrometry. We describe 12 viral peptides presented by HLA-A*0201 and 3 by HLA-B*0702. All HLA-A*0201 ligands participated in the memory response of MVA-immune donors, and several were immunogenic in Dryvax vaccinees. Eight epitopes were novel. Viral HLA ligand presentation and viral protein abundance did not correlate. All ligands were expressed early during the viral life cycle, and a pool of three of these mediated stronger protection against a lethal challenge in mice as compared with late epitopes. This highlights the reliability of the comparative mass spectrometry-based technique to identify relevant viral CD8(+) T cell epitopes for optimizing the monitoring of protective immune responses and the development of effective peptide-based vaccines.
authors.affiliation: Department of Immunology, Institute for Cell Biology, University of Tubingen, Tubingen, Germany.
authors.forename: Verena S
authors.initials: VS
authors.lastname: Meyer
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Kastenmuller
authors.forename: Georg
authors.initials: G
authors.lastname: Gasteiger
authors.forename: Mirita
authors.initials: M
authors.lastname: Franz-Wachtel
authors.forename: Tobias
authors.initials: T
authors.lastname: Lamkemeyer
authors.forename: Hans-Georg
authors.initials: HG
authors.lastname: Rammensee
authors.forename: Stefan
authors.initials: S
authors.lastname: Stevanovic
authors.forename: Dagmar
authors.initials: D
authors.lastname: Sigurdardottir
authors.forename: Ingo
authors.initials: I
authors.lastname: Drexler
mesh_terms: D017951:Antigen Presentation / Q000276:immunology; D002461:Cell Line, Transformed; D018984:Epitopes, T-Lymphocyte / Q000008:administration & dosage / Q000276:immunology / Q000378:metabolism / Q000502:physiology; D006680:HLA Antigens / Q000276:immunology* / Q000302:isolation & purification / Q000378:metabolism*; D015234:HLA-A Antigens / Q000276:immunology / Q000378:metabolism; D015789:HLA-A2 Antigen; D015235:HLA-B Antigens / Q000276:immunology / Q000378:metabolism; D015793:HLA-B7 Antigen; D015395:Histocompatibility Antigens Class I / Q000276:immunology* / Q000302:isolation & purification / Q000378:metabolism*; D006801:Humans; D007156:Immunologic Memory; D007553:Isotope Labeling / Q000379:methods*; D020014:K562 Cells; D008024:Ligands; D009856:Oncogene Proteins, Viral / Q000008:administration & dosage / Q000276:immunology / Q000378:metabolism / Q000502:physiology; D013602:T-Lymphocytes, Cytotoxic / Q000276:immunology / Q000378:metabolism / Q000821:virology; D014615:Vaccinia / Q000276:immunology* / Q000378:metabolism / Q000517:prevention & control*; D014616:Vaccinia virus / Q000276:immunology* / Q000378:metabolism; D014764:Viral Proteins / Q000008:administration & dosage / Q000276:immunology / Q000378:metabolism / Q000502:physiology; D017735:Virus Latency / Q000276:immunology
chemical_list: D018984:Epitopes, T-Lymphocyte; D006680:HLA Antigens; D015234:HLA-A Antigens; C435939:HLA-A*02:01 antigen; D015789:HLA-A2 Antigen; D015235:HLA-B Antigens; C477444:HLA-B*07:02 antigen; D015793:HLA-B7 Antigen; D015395:Histocompatibility Antigens Class I; D008024:Ligands; D009856:Oncogene Proteins, Viral; D014764:Viral Proteins